<template>
  <el-table :data="formatData" :row-style="showRow" v-bind="$attrs">
    <el-table-column v-if="columns.length===0" width="150">
      <template slot-scope="scope">
        <span v-for="space in scope.row._level" class="ms-tree-space" :key="space"></span>
        <span class="tree-ctrl" v-if="iconShow(0,scope.row)" @click="toggleExpanded(scope.$index)">
          <i v-if="!scope.row._expanded" class="el-icon-plus"></i>
          <i v-else class="el-icon-minus"></i>
        </span>
        {{scope.$index}}
      </template>
    </el-table-column>
    <el-table-column v-else v-for="(column, index) in columns" :key="column.value" :label="column.text" :width="column.width">
      <template slot-scope="scope">
        <template v-if="index === 0">
          <span v-for="space in scope.row._level" class="ms-tree-space" :key="space"></span>
        </template>
        <span class="tree-ctrl" v-if="iconShow(index,scope.row)" @click="toggleExpanded(scope.$index)">
          <i v-if="!scope.row._expanded" class="el-icon-plus"></i>
          <i v-else class="el-icon-minus"></i>
        </span>
        {{scope.row[column.value]}}
      </template>
    </el-table-column>
    <slot></slot>
  </el-table>
</template>

<script>
/**
  Auth: Lei.j1ang
  Created: 2018/1/19-13:59
*/
import treeToArray from './eval';
export default {
    name: 'treeTable',
    props: {
        data: {
            type: [Array, Object],
            required: true
        },
        columns: {
            type: Array,
            default: () => []
        },
        evalFunc: Function,
        evalArgs: Array,
        expandAll: {
            type: Boolean,
            default: false
        }
    },
    computed: {
    // 格式化数据源
        formatData: function() {
            let tmp;
            if (!Array.isArray(this.data)) {
                tmp = [this.data];
            } else {
                tmp = this.data;
            }
            const func = this.evalFunc || treeToArray;
            const args = this.evalArgs ? Array.concat([tmp, this.expandAll], this.evalArgs) : [tmp, this.expandAll];
            return func.apply(null, args);
        }
    },
    methods: {
        showRow: function(row) {
            const show = (row.row.parent ? (row.row.parent._expanded && row.row.parent._show) : true);
            row.row._show = show;
            return show ? 'animation:treeTableShow 1s;-webkit-animation:treeTableShow 1s;' : 'display:none;';
        },
        // 切换下级是否展开
        toggleExpanded: function(trIndex) {
            const record = this.formatData[trIndex];
            record._expanded = !record._expanded;
        },
        // 图标显示
        iconShow(index, record) {
            return (index === 0 && record.children && record.children.length > 0);
        }
    }
};
</script>
<style rel="stylesheet/css">
  @keyframes treeTableShow {
    from {opacity: 0;}
    to {opacity: 1;}
  }
  @-webkit-keyframes treeTableShow {
    from {opacity: 0;}
    to {opacity: 1;}
  }
</style>

<style lang="scss" rel="stylesheet/scss" scoped>
  $color-blue: #2196F3;
  $space-width: 18px;
  .ms-tree-space {
    position: relative;
    top: 1px;
    display: inline-block;
    font-style: normal;
    font-weight: 400;
    line-height: 1;
    width: $space-width;
    height: 14px;
    &::before {
      content: ""
    }
  }
  .processContainer{
    width: 100%;
    height: 100%;
  }
  table td {
    line-height: 26px;
  }

  .tree-ctrl{
    position: relative;
    cursor: pointer;
    color: $color-blue;
    margin-left: -$space-width;
  }
</style>
